US20120106150A1 - Illumination system for use in a stereolithography apparatus - Google Patents
Illumination system for use in a stereolithography apparatus Download PDFInfo
- Publication number
- US20120106150A1 US20120106150A1 US13/146,858 US201013146858A US2012106150A1 US 20120106150 A1 US20120106150 A1 US 20120106150A1 US 201013146858 A US201013146858 A US 201013146858A US 2012106150 A1 US2012106150 A1 US 2012106150A1
- Authority
- US
- United States
- Prior art keywords
- leds
- illumination system
- levelling
- led
- layer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C64/00—Additive manufacturing, i.e. manufacturing of three-dimensional [3D] objects by additive deposition, additive agglomeration or additive layering, e.g. by 3D printing, stereolithography or selective laser sintering
- B29C64/10—Processes of additive manufacturing
- B29C64/106—Processes of additive manufacturing using only liquids or viscous materials, e.g. depositing a continuous bead of viscous material
- B29C64/124—Processes of additive manufacturing using only liquids or viscous materials, e.g. depositing a continuous bead of viscous material using layers of liquid which are selectively solidified
- B29C64/129—Processes of additive manufacturing using only liquids or viscous materials, e.g. depositing a continuous bead of viscous material using layers of liquid which are selectively solidified characterised by the energy source therefor, e.g. by global irradiation combined with a mask
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S362/00—Illumination
- Y10S362/80—Light emitting diode
Definitions
- the invention relates to the field of stereolithography, and more in particular to an illumination system for use in a stereolithography apparatus.
- stereolithography also known as 3D-printing, is a rapid prototyping technology for producing parts with high accuracy.
- stereolithography may utilize a vat of liquid light-curable photopolymer resin and a computer controlled UV-laser to cure the resin, one layer at a time.
- the construction process is essentially cyclic. For each layer that corresponds to a slice of the part to be produced, the spot of the laser beam traces the respective cross-sectional pattern on the surface of the liquid resin. Exposure to the laser light cures or solidifies the traced pattern, and adheres it to the layer below.
- the part in the making which may rest on an elevator platform immersed in the vat of photopolymer resin—may be lowered by a single layer thickness such that its top layer is positioned just below the surface of the resin again, allowing the next layer to be built. This sequence of steps is continued until the part is finished.
- the stereolithography apparatus may be fitted with an illumination system comprising two-dimensional arrays of LEDs and lenses to provide for selective illumination of the photopolymer resin.
- the illumination system as a whole may be moveably disposed relative to the location of the workpiece, while the LEDs may be rigidly connected to one another and the lenses.
- the lenses may serve to image the light-emitting surfaces of the LEDs onto the surface of the photopolymer resin.
- each LED is associated with its own conjugate image spot, such that an array comprising a certain number of LEDs may produce just as many image spots.
- the illumination system may be scanningly moved relative to the vat holding the photopolymer resin, while the individual LEDs may be selectively switched on and off so as to illuminate the surface of the resin according to the cross-sectional pattern of the layer to be solidified.
- an illumination system based on LED lighting is relatively inexpensive. In addition, it offers an equally high accuracy at greater production speeds.
- an illumination system capable of illuminating a photopolymer resin to high accuracy, so as to allow even very fine details of a workpiece to be fabricated must be capable of producing sufficiently bright image spots with well defined dimensions at well-defined positions.
- the requirement of sufficient brightness leads to an optical system with a high numerical aperture, since a higher numerical aperture enables the optical system to collect more light from the LEDs.
- a high numerical aperture may be accompanied by a high sensitivity of the image spot dimensions to the precise LED positions.
- the invention provides an illumination system suitable for use in a stereolithography apparatus, comprising: a plurality of light-emitting diodes (LEDs), each LED having at least a first, light-emitting surface and a second surface, at least one of the first and the second surface being substantially flat; a plurality of electrical pathways, selectively connected to the respective LEDs, such that each LED can be individually controlled; and a levelling surface, wherein the levelling surface is substantially flat and in levelling contact with the at least one substantially flat surface of each LED, such that a two-dimensional array of LEDs extends in a plane parallel to the levelling surface.
- LEDs light-emitting diodes
- the LEDs are brought into levelling contact with a substantially flat levelling surface.
- substantially flat refers to surfaces having a surface flatness of less than about 10 ⁇ m, and preferably less than 5 ⁇ m. Such a degree of surface flatness may for example be achieved through optical polishing.
- the levelling surface may, for example, be provided by a mechanical carrier or support body, or by a multi-lens array, as will be elucidated below. It is noted that a levelling surface may be made up of multiple, separate levelling surfaces that extend in the same plane. The term levelling surface is thus not necessarily to be construed as meaning a single, continuous surface. See for example FIG. 2 and the discussion thereof below.
- the illumination system according to the invention may be manufactured using diced, but unpackaged LEDs: so-called bare dies.
- the underlying insight is concerned with the fact that common surface mount LEDs are embedded in an IC-package, which package—when being handled by a pick-and-place robot—serves as a reference. Since the outer dimensions of the IC-package may well exceed the desired positional tolerance for the LED packaged inside, it may be impossible for the robot to position surface mount LEDs with the desired accuracy.
- a pick-and-place robot may determine the precise location of a bare die, and position it accordingly.
- dicing the wafer allows for very efficient use of wafer material and thus contributes to an economical production process.
- Doing away with the IC-package also means disposing of a thermally insulating barrier between the actual LED and the support body to which the LED is thermally coupled. The operational temperature of the LED may therefore be lower, which is beneficial to its life span and light output.
- the levelling surface is provided by a substantially rigid support body that comprises at least a first layer, which layer provides the levelling surface, and which layer comprises a material having a thermal conductivity of at least 150 W/mK.
- a levelling surface to which the LEDs are thermally coupled may preferably comprise a material having a large thermal conductivity, for example >150 W/mK, such as copper or aluminium.
- the support body may comprise multiple layers.
- the support body may, for example, comprise a base of Invar, topped with a relatively thin layer of copper that provides the levelling surface.
- the copper layer which possesses a thermal conductivity >150 W/mK may contact the second surfaces of the LEDs, and allow the LEDs to give off their heat.
- the copper layer will spread the heat, and transfer it on to the base of Invar, which has a lower thermal conductivity but a more favourable (i.e. lower) thermal expansion coefficient.
- the base of Invar will limit changes in the relative positions of the LEDs due to even or uneven heating of the base by the LEDs.
- any such base layer preferably has a linear thermal expansion coefficient (i.e. fractional increase in length per degree of temperature change) of 5.10 ⁇ 6 /K or less.
- a substantially rigid support body may be fitted with structural characteristics that allow it suitably transfer heat.
- the support body may, for example, be provided with one or more cooling channels through which—during use—a cooling fluid may be circulated, and/or cooling fins capable of dissipating LED generated heat.
- FIG. 1 is a schematic sectional view of an exemplary stereolithography apparatus in which the illumination system according to the present invention may be used;
- FIGS. 2-4 schematically illustrate certain embodiments of an illumination system according to the present invention.
- FIGS. 5A and 5B show a schematic side view and a perspective view of a further embodiment.
- FIG. 1 shows a sectional side view of an exemplary stereolithography apparatus (SLA) 1 in which the illumination system according to the present invention may be implemented.
- the SLA 1 may be used for the layerwise production of a tangible object 2 , such as a prototype or model of an article of manufacture.
- the SLA 1 comprises a carrier plate 4 , a liquid reservoir 10 , and an illumination system 30 .
- the tangible object 2 is suspended from the Carrier plate 4 to which the first-constructed layer of the object 2 , and indirectly also any subsequent layers, adhere.
- the carrier plate 4 is moveable in a direction 6 by means of a drive mechanism (not shown), and is moved upward one layer thickness each time a new layer has been constructed.
- the liquid reservoir 10 is filled with a liquid, photo-curable resin 14 .
- a bottom plate 12 of the liquid reservoir 10 is optically transparent to the light emitted by the illumination system 30 , which is to be described hereafter.
- the bottom plate 12 also functions as a construction shape that bounds one side of a liquid layer 16 to be (partially) solidified. It will be clear that once a layer has been constructed, and the carrier plate 4 is moved upward one layer thickness, the space between the lastly constructed layer and the bottom plate 12 is filled with resin 14 , so as to form said liquid layer 16 .
- the SLA 1 also comprises an illumination system 30 that is adapted to selectively illuminate a predetermined area of the liquid layer 16 .
- an illumination system 30 that is adapted to selectively illuminate a predetermined area of the liquid layer 16 .
- a solid layer 18 of the tangible object 2 may be obtained, said layer 18 having a predetermined shape in accordance with the applied illumination pattern.
- the illumination system 30 includes an LED array 32 and an imaging system that comprises two multi-lens arrays 40 , 42 .
- the imaging system may comprise a different number of multi-lens arrays, for example just one, and/or other elements, depending on the desired configuration.
- a numerical aperture in the range of 0.3-0.8 or even higher then 0.8 slight changes in the position of an LED may have enlarged effects on the dimensions of its conjugate image spot.
- the image spots in question may have a diameter on the order of 100 ⁇ m, whereby effective spot separation distances of 50 ⁇ m may be effected. If an LED would be positioned 10 ⁇ m from its ideal position (in a direction parallel to the optical axis of the optical system), this deviation might cause an increase in image spot diameter of about 30 ⁇ m. Obviously, this is a significant and in fact unacceptable aberration.
- Deviations of the LEDs from their ideal positions in directions perpendicular to the optical axis of the optical system may not be enlarged, but merely passed on to the image. Still, when aiming for an effective spot separation distance of 50 ⁇ m or less, deviations of 10 ⁇ m may seriously impair the resolution of the system.
- the desire to use an optical system having a high numerical aperture translates, inter alia, into relative positioning tolerances for the LEDs.
- the presently desired positional tolerances for the LEDs are less than 10 ⁇ m in each of the x, y and z directions, wherein the x-y plane is the plane of the two-dimensional LED array and the z-direction extends in a direction perpendicular thereto.
- Such precise positioning seems unattainable using common surface mount LEDs mounted on (multi layered) printed circuit boards.
- a monolithic array of LEDs i.e. a complete wafer (section) comprising a plurality of LEDs, offers an alternative that excels in positional accuracy of the individual LEDs. This is because the wafer manufacturing process itself warrants the exactitude.
- the desired separation distance between neighbouring LEDs in the array increases, more precious wafer material is essentially wasted. At typical separation distances of about 1 mm and more, the costs of using of a monolithic array become unacceptably high.
- the LED array 32 comprises a plurality of LEDs 34 .
- the LEDs 34 are arranged in a two-dimensional plane, preferably in a grid-like fashion, such that the LEDs compose equidistant and perpendicularly oriented rows and columns with each LED defining a gridpoint.
- Each of the LEDs 34 possesses a light-emitting surface 36 that faces the bottom plate 12 of the liquid reservoir 10 , which is substantially parallel to the two-dimensional plane of the LED array 32 .
- a controller 38 may be provided to control, i.e. switch off and on (with desired intensity), individual LEDs 34 in the array 32 so as to create a time-varying two-dimensional pattern of lighted LEDs that may be projected onto the liquid resin layer 16 .
- the substantially planar multi-lens arrays 40 , 42 are disposed in between the light-emitting surfaces 36 of the LEDs 34 and the liquid layer 16 to be selectively cured.
- Each of the arrays 40 , 42 comprises a plurality of lenses 44 , preferably one for each LED 34 .
- the lenses 44 may preferably be arranged in correspondence with the arrangement of the LEDs 34 in the array 32 .
- the multi-lens arrays 40 , 42 may be of the plano-convex type, thus having one plano side 46 that defines the plano side of all lenses 44 , and a plurality of convex, partially spheroidally shaped sections 48 , one for each lens 42 .
- the multi-lens arrays 40 , 42 may be oppositely oriented, as shown in FIG. 1 . Together, the multi-lens arrays 40 , 42 form an imaging system that is adapted to image a pattern of lighted LEDs onto the liquid layer 16 in such a way, that each lighted LED 34 produces a separate, conjugate spot on a predetermined area of the liquid layer 16 .
- the multi-lens arrays 40 , 42 may be made of a variety of materials, including glass, fused silica and plastic.
- the illumination system 30 may be moveably disposed below the bottom plate 12 of the liquid reservoir 10 , such that it can move in a direction 8 parallel to the bottom plate 12 of the liquid reservoir 10 .
- the motion of the illumination system 30 may be controlled by the aforementioned controller 38 , which also controls the lighting of the LEDs 34 .
- the illumination system 30 may be moved rectilinearly in a direction that extends at an angle with the directions of the rows and columns of the LED array 32 to enhance the effective resolution of the system. This technique is described in more detail in copending application EP 07150447.6 in the name of applicant, which is incorporated herein by reference for further information regarding this aspect.
- FIG. 2-4 schematically show certain embodiments thereof in more detail.
- FIG. 2 is a schematic sectional view of an embodiment of an illumination system 30 according to the present invention.
- FIG. 2 depicts a support body 50 and electrical pathways 56 .
- the LEDs 34 which in the embodiment of FIG. 2 are bare dies, are in mechanical and thermal contact with the support body 50 through their second surfaces 37 .
- the support body 50 which may be a plate or otherwise suitably shaped body, may be partially made of material having a large thermal conductivity, e.g. >150 W/mK, such as aluminium or copper. Good thermal conductivity allows the support body to serve as a heat sink, and to divert excessive heat away from the LEDs 34 in order to increase their life-expectancy and to prevent degradation of their light output. It may also prevent mutually uneven heating of the LEDs 34 , which might lead to uneven light-production across the array 32 .
- the top surface of the support body is polished, for example optically, to obtain a smooth and substantially flat levelling surface 52 .
- the surface flatness of the polished levelling surface 52 may be less than 10 ⁇ m, and preferably less than 5 ⁇ m.
- slots may be machined into the upper side of support body 50 .
- the slots accommodate the electrical pathways 56 , whereas the ribs 54 between them provide for mechanical support of the LEDs 34 .
- the ribs 54 Due to the method of construction, the ribs 54 have substantially flat top surfaces 52 that all extend in the same plane. Together, they may therefore be considered a ‘levelling surface’ in the meaning of this text.
- the substantially flat second surfaces 37 of the LEDs 34 may be attached to the levelling surface 52 by means of a thin layer of adhesive.
- the adhesive may preferably be thermally conductive. If desired, the adhesive may also contain spacers, such as glass or polystyrene spheres, to help set the exact distance between the levelling surface 52 and the second surfaces 37 of the LEDs 34 .
- An exact separation distance not only contributes to the positional accuracy of the LEDs 34 , but also precisely defines the bond layer thickness between the LEDs and the levelling surface 52 . As the thickness of the bond layer is approximately proportional to the thermal resistance of the layer, constancy of the bond layer thickness for all LEDs 34 in the array is a feature that counteracts their uneven heating and degradation.
- the electrical pathways 56 may be provided for in the form of multi-layered printed-circuit board (PCB).
- Multi-layered PCBs allow for a high density of electrical pathways 56 , which is a practical requirement due to the relatively compact packing of the LEDs 34 .
- Every 1-2 mm 2 of levelling surface 52 may typically be provided with an LED 34 , while an illumination system 30 may comprise many thousands of individually controllable LEDs altogether.
- the electrical pathways 56 are, at least partly, disposed in the slots between the ribs 54 . This configuration prevents the pathways 56 from forming an obstruction to light that is radiated by the LEDs 34 towards the multi lens array 40 .
- the electrical connections of the LEDs 34 to the electrical pathways 56 may be effected through wire bonds 58 , which may selectively connect the electrical contact pads of the bare die LEDs to the electrical pathways 56 .
- FIG. 3 shows a second, alternative embodiment of the illumination system 30 .
- a ceramic support body 50 having a high thermal conductivity is used.
- the support body 50 may additionally be fitted with one of more channels 60 through which a cooling fluid may be circulated.
- the ceramic support body 50 shown in FIG. 3 has a single, continuous levelling surface 52 .
- This levelling surface 52 has been polished to obtain the desired degree of surface flatness. No slots are machined into the support body 50 during manufacture to accommodate the electrical pathways 56 . Instead, the electrical pathways 56 are provided for by thick film layers that may be applied to the levelling surface 52 by means of, for example, screen printing.
- Wire bonds 58 may be used to selective connect the electrical contact pads of the bare die LEDs 34 to the respective conductive layers.
- the LEDs 34 may be attached to the levelling surface 52 by means of a preferably thermally conductive adhesive, comprising spacers or not.
- the support body 50 provides for mechanical support and the thermal cooling of the LEDs 34 .
- the supply of electrical power is taken care of by the electrical pathways 56 .
- This situation is to be distinguished from a more traditional setup wherein surface mount LEDs are simply placed onto a PCB, which PCB is to fulfil all three functions.
- Such a setup does not allow for accurate positioning of the LEDs, in particular because multi-layered PCB usually have an unacceptably large z-tolerance.
- FIG. 4 shows an embodiment wherein the LEDs 34 are nevertheless positioned on a multi-layered PCB, which itself is provided on the upper surface of a support body 50 .
- the accurate z-alignment of the LEDs 34 is not accomplished by means of the PCB, but by means of attachment of the LEDs 34 to the plano side 46 of the multi-lens array 40 , which side 46 serves as a levelling surface.
- the employed LEDs 34 are preferably so-called (bare die) flip-chips. Their light-emitting surfaces 36 are free of electrical contact pads, and therefore substantially flat.
- the light-emitting surfaces 36 of the flip-chip LEDs 34 may be adhered to the substantially flat plano side 46 of the multi-lens array 40 using an optically transparent adhesive, so as to obtain proper z-alignment.
- the LEDs 34 may first be attached to the plano side 46 of the multi-lens array 40 , and then—after any adhesive has set and the relative positions of the LEDs 34 are fixed—be connected to the electrical pathways 56 of the PCB, e.g. using ultrasound soldering or an anisotropic conductive adhesive.
- the LEDs may not be glued to the multi-lens array.
- the LEDs 34 may, for example, first be connected to the electrical pathways 56 of the PCB, whereby a flexible adhesive may be provided between the second surfaces 37 of the LEDs 34 and the top surface of the PCB. Subsequently, the multi-lens array 40 may be put in place, such that its plano side 46 presses gently against the light-emitting surfaces 36 of the LEDs 34 to align them in the z-direction. When all LEDs 34 are properly aligned, the flexible adhesive may be cured to permanently fix the relative orientations of the LEDs.
- An advantage of the first embodiment is that the LEDs 34 are fixed to the multi-lens array 40 with high positional accuracy.
- FIGS. 5A and 5B show a schematic side view and a perspective view respectively, of a further embodiment having slots 55 accommodating PCB 56 , whereas the ribs 54 between the slots 55 provide for mechanical support of the LEDs 34 . It is shown that multiple LEDS 34 may be provided on the surface 52 ; which are groupwise controlled by electrical circuitry arranged on the PCB 56 in the slots 55 . This provides a thermal benefit as the LEDs are not each positioned on narrow ribs dimensioned to the LED interdistance, which could otherwise limit thermal conductivity to the cooling channels 60 .
- the electrical pathway structures 56 on PCB may be stacked in a vertical configuration, that is, the PCB extending in a plane transverse to the levelling surface 52 . This optimizes the gap distance which can be kept minimal between subsequent LEDs 34 .
- the illustrated PCB structure 56 extends in addition, in the preferred embodiment in the plane of the levelling surface 56 , and has openings 59 to accommodate LEDs 34 that are directly provided on the levelling surface.
- the openings are made substantially larger than the size of the LEDs, such that the tolerance on the position of the PCB with respect to the LEDs is high.
- the PCB 56 is a flex type PCB and is folded such that at least the part with ICs 57 fits in the slots 55 and the part with the holes for the LEDs lies flat on the substrate 50 .
Abstract
-
- a plurality of light-emitting diodes (LEDs) (34), each LED having at least a first, light-emitting surface (36) and a second surface (37), at least one of the first and the second surface being substantially flat;
- a plurality of electrical pathways (56), selectively connected to the respective LEDs, such that each LED can be individually controlled; and
- a levelling surface (46, 52),
Description
- The invention relates to the field of stereolithography, and more in particular to an illumination system for use in a stereolithography apparatus.
- Stereolithography, also known as 3D-printing, is a rapid prototyping technology for producing parts with high accuracy. In a simple implementation stereolithography may utilize a vat of liquid light-curable photopolymer resin and a computer controlled UV-laser to cure the resin, one layer at a time. The construction process is essentially cyclic. For each layer that corresponds to a slice of the part to be produced, the spot of the laser beam traces the respective cross-sectional pattern on the surface of the liquid resin. Exposure to the laser light cures or solidifies the traced pattern, and adheres it to the layer below. Once a layer has been cured, the part in the making—which may rest on an elevator platform immersed in the vat of photopolymer resin—may be lowered by a single layer thickness such that its top layer is positioned just below the surface of the resin again, allowing the next layer to be built. This sequence of steps is continued until the part is finished.
- Instead of with a laser, the stereolithography apparatus may be fitted with an illumination system comprising two-dimensional arrays of LEDs and lenses to provide for selective illumination of the photopolymer resin. The illumination system as a whole may be moveably disposed relative to the location of the workpiece, while the LEDs may be rigidly connected to one another and the lenses. The lenses may serve to image the light-emitting surfaces of the LEDs onto the surface of the photopolymer resin. Preferably, each LED is associated with its own conjugate image spot, such that an array comprising a certain number of LEDs may produce just as many image spots. During production, the illumination system may be scanningly moved relative to the vat holding the photopolymer resin, while the individual LEDs may be selectively switched on and off so as to illuminate the surface of the resin according to the cross-sectional pattern of the layer to be solidified. Compared to a laser, an illumination system based on LED lighting is relatively inexpensive. In addition, it offers an equally high accuracy at greater production speeds.
- Manufacturing a reliable illumination system in an economical fashion has been found problematic. A primary reason for this, is that an illumination system capable of illuminating a photopolymer resin to high accuracy, so as to allow even very fine details of a workpiece to be fabricated, must be capable of producing sufficiently bright image spots with well defined dimensions at well-defined positions. The requirement of sufficient brightness leads to an optical system with a high numerical aperture, since a higher numerical aperture enables the optical system to collect more light from the LEDs. However, a high numerical aperture may be accompanied by a high sensitivity of the image spot dimensions to the precise LED positions.
- It is an object of the present invention to provide for an LED economically manufacturable illumination system, whose design allows it to be used in combination with an optical system having a high numerical aperture.
- To this end, the invention provides an illumination system suitable for use in a stereolithography apparatus, comprising: a plurality of light-emitting diodes (LEDs), each LED having at least a first, light-emitting surface and a second surface, at least one of the first and the second surface being substantially flat;
a plurality of electrical pathways, selectively connected to the respective LEDs, such that each LED can be individually controlled; and a levelling surface, wherein the levelling surface is substantially flat and in levelling contact with the at least one substantially flat surface of each LED, such that a two-dimensional array of LEDs extends in a plane parallel to the levelling surface. - To obtain the desired accuracy in the z-direction, the LEDs are brought into levelling contact with a substantially flat levelling surface. The term ‘substantially flat’ refers to surfaces having a surface flatness of less than about 10 μm, and preferably less than 5 μm. Such a degree of surface flatness may for example be achieved through optical polishing. The levelling surface may, for example, be provided by a mechanical carrier or support body, or by a multi-lens array, as will be elucidated below. It is noted that a levelling surface may be made up of multiple, separate levelling surfaces that extend in the same plane. The term levelling surface is thus not necessarily to be construed as meaning a single, continuous surface. See for example
FIG. 2 and the discussion thereof below. - To obtain a sufficient positional accuracy in the x-y plane, i.e. the plane of the two-dimensional LED array, or to improve the positional accuracy therein, the illumination system according to the invention may be manufactured using diced, but unpackaged LEDs: so-called bare dies. The underlying insight is concerned with the fact that common surface mount LEDs are embedded in an IC-package, which package—when being handled by a pick-and-place robot—serves as a reference. Since the outer dimensions of the IC-package may well exceed the desired positional tolerance for the LED packaged inside, it may be impossible for the robot to position surface mount LEDs with the desired accuracy. However, without the obscuring presence of an IC-package a pick-and-place robot may determine the precise location of a bare die, and position it accordingly. Compared to for example the use of a monolithic array, dicing the wafer allows for very efficient use of wafer material and thus contributes to an economical production process. Doing away with the IC-package also means disposing of a thermally insulating barrier between the actual LED and the support body to which the LED is thermally coupled. The operational temperature of the LED may therefore be lower, which is beneficial to its life span and light output.
- According to an aspect of the invention, the levelling surface is provided by a substantially rigid support body that comprises at least a first layer, which layer provides the levelling surface, and which layer comprises a material having a thermal conductivity of at least 150 W/mK.
- It is a known fact that LEDs exhibit a light output sensitivity to temperature, and in fact are permanently degraded by excessive temperature. To promote the life-expectancy of an LED array, and equally important: the homogeneity of its light output, care is taken to ensure that the LEDs are not excessively and/or unevenly heated. To this end, a levelling surface to which the LEDs are thermally coupled may preferably comprise a material having a large thermal conductivity, for example >150 W/mK, such as copper or aluminium. In some embodiments, the support body may comprise multiple layers. The support body may, for example, comprise a base of Invar, topped with a relatively thin layer of copper that provides the levelling surface. The copper layer, which possesses a thermal conductivity >150 W/mK may contact the second surfaces of the LEDs, and allow the LEDs to give off their heat. The copper layer will spread the heat, and transfer it on to the base of Invar, which has a lower thermal conductivity but a more favourable (i.e. lower) thermal expansion coefficient. The base of Invar will limit changes in the relative positions of the LEDs due to even or uneven heating of the base by the LEDs. In general, any such base layer preferably has a linear thermal expansion coefficient (i.e. fractional increase in length per degree of temperature change) of 5.10−6/K or less.
- Alternatively or in addition to material choices, a substantially rigid support body may be fitted with structural characteristics that allow it suitably transfer heat. The support body may, for example, be provided with one or more cooling channels through which—during use—a cooling fluid may be circulated, and/or cooling fins capable of dissipating LED generated heat.
- The above-mentioned and other features and advantages of the invention will be more fully understood from the following detailed description of certain embodiments of the invention, taken together with the accompanying drawings that are meant to illustrate and not to limit the invention.
-
FIG. 1 is a schematic sectional view of an exemplary stereolithography apparatus in which the illumination system according to the present invention may be used; and -
FIGS. 2-4 schematically illustrate certain embodiments of an illumination system according to the present invention. -
FIGS. 5A and 5B show a schematic side view and a perspective view of a further embodiment. - In the drawings, identical reference numbers identify similar elements. The sizes, shapes, relative positions and angles of elements in the drawings are not necessarily drawn to scale, and some of these elements may be arbitrarily enlarged and positioned to improve drawing legibility. Further, the particular shapes of the elements as drawn are not intended to convey any information regarding the actual shape of the particular elements, and may have been solely selected for ease of recognition in the drawings.
- Reference is first made to
FIG. 1 , which shows a sectional side view of an exemplary stereolithography apparatus (SLA) 1 in which the illumination system according to the present invention may be implemented. The SLA 1 may be used for the layerwise production of atangible object 2, such as a prototype or model of an article of manufacture. TheSLA 1 comprises acarrier plate 4, aliquid reservoir 10, and anillumination system 30. - During production, the
tangible object 2 is suspended from theCarrier plate 4 to which the first-constructed layer of theobject 2, and indirectly also any subsequent layers, adhere. Thecarrier plate 4 is moveable in adirection 6 by means of a drive mechanism (not shown), and is moved upward one layer thickness each time a new layer has been constructed. - The
liquid reservoir 10 is filled with a liquid, photo-curable resin 14. Abottom plate 12 of theliquid reservoir 10 is optically transparent to the light emitted by theillumination system 30, which is to be described hereafter. Thebottom plate 12 also functions as a construction shape that bounds one side of aliquid layer 16 to be (partially) solidified. It will be clear that once a layer has been constructed, and thecarrier plate 4 is moved upward one layer thickness, the space between the lastly constructed layer and thebottom plate 12 is filled withresin 14, so as to form saidliquid layer 16. - The
SLA 1 also comprises anillumination system 30 that is adapted to selectively illuminate a predetermined area of theliquid layer 16. As a result of the illumination, asolid layer 18 of thetangible object 2 may be obtained, saidlayer 18 having a predetermined shape in accordance with the applied illumination pattern. Theillumination system 30 includes anLED array 32 and an imaging system that comprises twomulti-lens arrays - At a high numerical aperture for example, a numerical aperture in the range of 0.3-0.8 or even higher then 0.8 slight changes in the position of an LED may have enlarged effects on the dimensions of its conjugate image spot. By way of example: the image spots in question may have a diameter on the order of 100 μm, whereby effective spot separation distances of 50 μm may be effected. If an LED would be positioned 10 μm from its ideal position (in a direction parallel to the optical axis of the optical system), this deviation might cause an increase in image spot diameter of about 30 μm. Obviously, this is a significant and in fact unacceptable aberration. Deviations of the LEDs from their ideal positions in directions perpendicular to the optical axis of the optical system may not be enlarged, but merely passed on to the image. Still, when aiming for an effective spot separation distance of 50 μm or less, deviations of 10 μm may seriously impair the resolution of the system.
- Thus, the desire to use an optical system having a high numerical aperture translates, inter alia, into relative positioning tolerances for the LEDs. As illustrated, the presently desired positional tolerances for the LEDs are less than 10 μm in each of the x, y and z directions, wherein the x-y plane is the plane of the two-dimensional LED array and the z-direction extends in a direction perpendicular thereto. Such precise positioning seems unattainable using common surface mount LEDs mounted on (multi layered) printed circuit boards. The dimensional tolerances of the LEDs may easily exceed the above-mentioned 10 μm, disabling a pick-and-place robot to position them with the desired accuracy, while multi-layer printed circuit boards—which provide for the electrical connections to each individual LED—are difficult to flatten, in particular across the relatively large surface areas required by LED arrays. In contrast, a monolithic array of LEDs, i.e. a complete wafer (section) comprising a plurality of LEDs, offers an alternative that excels in positional accuracy of the individual LEDs. This is because the wafer manufacturing process itself warrants the exactitude. However, when the desired separation distance between neighbouring LEDs in the array increases, more precious wafer material is essentially wasted. At typical separation distances of about 1 mm and more, the costs of using of a monolithic array become unacceptably high.
- Though positional accuracy of the LEDs is a principle problem in itself, additional design requirements must be met as well. These requirements include the individual controllability of each LED, which requires individual electrical pathways to each LED, and a good thermal management system that prevents fast and/or uneven degradation of the LEDs due to their unfavourable sensitivity to high temperatures.
- The
LED array 32 comprises a plurality ofLEDs 34. TheLEDs 34 are arranged in a two-dimensional plane, preferably in a grid-like fashion, such that the LEDs compose equidistant and perpendicularly oriented rows and columns with each LED defining a gridpoint. Each of theLEDs 34 possesses a light-emittingsurface 36 that faces thebottom plate 12 of theliquid reservoir 10, which is substantially parallel to the two-dimensional plane of theLED array 32. Acontroller 38 may be provided to control, i.e. switch off and on (with desired intensity),individual LEDs 34 in thearray 32 so as to create a time-varying two-dimensional pattern of lighted LEDs that may be projected onto theliquid resin layer 16. - The substantially planar
multi-lens arrays surfaces 36 of theLEDs 34 and theliquid layer 16 to be selectively cured. Each of thearrays lenses 44, preferably one for eachLED 34. Thelenses 44 may preferably be arranged in correspondence with the arrangement of theLEDs 34 in thearray 32. Themulti-lens arrays plano side 46 that defines the plano side of alllenses 44, and a plurality of convex, partially spheroidally shapedsections 48, one for eachlens 42. Themulti-lens arrays FIG. 1 . Together, themulti-lens arrays liquid layer 16 in such a way, that each lightedLED 34 produces a separate, conjugate spot on a predetermined area of theliquid layer 16. Themulti-lens arrays - The
illumination system 30 may be moveably disposed below thebottom plate 12 of theliquid reservoir 10, such that it can move in adirection 8 parallel to thebottom plate 12 of theliquid reservoir 10. The motion of theillumination system 30 may be controlled by theaforementioned controller 38, which also controls the lighting of theLEDs 34. In use, theillumination system 30 may be moved rectilinearly in a direction that extends at an angle with the directions of the rows and columns of theLED array 32 to enhance the effective resolution of the system. This technique is described in more detail in copending application EP 07150447.6 in the name of applicant, which is incorporated herein by reference for further information regarding this aspect. - Now that the operational context of the
illumination system 30 has been clarified, attention is invited toFIG. 2-4 , which schematically show certain embodiments thereof in more detail. -
FIG. 2 is a schematic sectional view of an embodiment of anillumination system 30 according to the present invention. In addition to theLEDs 34 and themulti-lens arrays FIG. 1 ,FIG. 2 depicts asupport body 50 andelectrical pathways 56. - The
LEDs 34, which in the embodiment ofFIG. 2 are bare dies, are in mechanical and thermal contact with thesupport body 50 through theirsecond surfaces 37. Thesupport body 50, which may be a plate or otherwise suitably shaped body, may be partially made of material having a large thermal conductivity, e.g. >150 W/mK, such as aluminium or copper. Good thermal conductivity allows the support body to serve as a heat sink, and to divert excessive heat away from theLEDs 34 in order to increase their life-expectancy and to prevent degradation of their light output. It may also prevent mutually uneven heating of theLEDs 34, which might lead to uneven light-production across thearray 32. During manufacture, the top surface of the support body is polished, for example optically, to obtain a smooth and substantiallyflat levelling surface 52. The surface flatness of thepolished levelling surface 52 may be less than 10 μm, and preferably less than 5 μm. After the polishing treatment, slots may be machined into the upper side ofsupport body 50. In the embodiment ofFIG. 2 , the slots accommodate theelectrical pathways 56, whereas theribs 54 between them provide for mechanical support of theLEDs 34. Due to the method of construction, theribs 54 have substantially flattop surfaces 52 that all extend in the same plane. Together, they may therefore be considered a ‘levelling surface’ in the meaning of this text. The substantially flatsecond surfaces 37 of theLEDs 34 may be attached to the levellingsurface 52 by means of a thin layer of adhesive. The adhesive may preferably be thermally conductive. If desired, the adhesive may also contain spacers, such as glass or polystyrene spheres, to help set the exact distance between the levellingsurface 52 and thesecond surfaces 37 of theLEDs 34. An exact separation distance not only contributes to the positional accuracy of theLEDs 34, but also precisely defines the bond layer thickness between the LEDs and the levellingsurface 52. As the thickness of the bond layer is approximately proportional to the thermal resistance of the layer, constancy of the bond layer thickness for allLEDs 34 in the array is a feature that counteracts their uneven heating and degradation. - The
electrical pathways 56 may be provided for in the form of multi-layered printed-circuit board (PCB). Multi-layered PCBs allow for a high density ofelectrical pathways 56, which is a practical requirement due to the relatively compact packing of theLEDs 34. Every 1-2 mm2 of levellingsurface 52, for example, may typically be provided with anLED 34, while anillumination system 30 may comprise many thousands of individually controllable LEDs altogether. As mentioned, theelectrical pathways 56 are, at least partly, disposed in the slots between theribs 54. This configuration prevents thepathways 56 from forming an obstruction to light that is radiated by theLEDs 34 towards themulti lens array 40. The electrical connections of theLEDs 34 to theelectrical pathways 56 may be effected throughwire bonds 58, which may selectively connect the electrical contact pads of the bare die LEDs to theelectrical pathways 56. -
FIG. 3 shows a second, alternative embodiment of theillumination system 30. In this embodiment, aceramic support body 50 having a high thermal conductivity is used. To further promote the discharge of heat, thesupport body 50 may additionally be fitted with one ofmore channels 60 through which a cooling fluid may be circulated. In contrast to the embodiment ofFIG. 2 , theceramic support body 50 shown inFIG. 3 has a single,continuous levelling surface 52. This levellingsurface 52 has been polished to obtain the desired degree of surface flatness. No slots are machined into thesupport body 50 during manufacture to accommodate theelectrical pathways 56. Instead, theelectrical pathways 56 are provided for by thick film layers that may be applied to the levellingsurface 52 by means of, for example, screen printing. The schematically depicted stacks of layers shown inFIG. 3 may be made up of alternately conductive and non-conductive layers.Wire bonds 58 may be used to selective connect the electrical contact pads of thebare die LEDs 34 to the respective conductive layers. As in the embodiment ofFIG. 2 , theLEDs 34 may be attached to the levellingsurface 52 by means of a preferably thermally conductive adhesive, comprising spacers or not. - In the embodiments of
FIGS. 2 and 3 , thesupport body 50 provides for mechanical support and the thermal cooling of theLEDs 34. The supply of electrical power is taken care of by theelectrical pathways 56. This situation is to be distinguished from a more traditional setup wherein surface mount LEDs are simply placed onto a PCB, which PCB is to fulfil all three functions. Such a setup does not allow for accurate positioning of the LEDs, in particular because multi-layered PCB usually have an unacceptably large z-tolerance. -
FIG. 4 shows an embodiment wherein theLEDs 34 are nevertheless positioned on a multi-layered PCB, which itself is provided on the upper surface of asupport body 50. The accurate z-alignment of theLEDs 34, however, is not accomplished by means of the PCB, but by means of attachment of theLEDs 34 to theplano side 46 of themulti-lens array 40, whichside 46 serves as a levelling surface. To allow for such a configuration, the employedLEDs 34 are preferably so-called (bare die) flip-chips. Their light-emittingsurfaces 36 are free of electrical contact pads, and therefore substantially flat. In one embodiment, the light-emittingsurfaces 36 of the flip-chip LEDs 34 may be adhered to the substantiallyflat plano side 46 of themulti-lens array 40 using an optically transparent adhesive, so as to obtain proper z-alignment. During manufacture, theLEDs 34 may first be attached to theplano side 46 of themulti-lens array 40, and then—after any adhesive has set and the relative positions of theLEDs 34 are fixed—be connected to theelectrical pathways 56 of the PCB, e.g. using ultrasound soldering or an anisotropic conductive adhesive. In an alternative embodiment, the LEDs may not be glued to the multi-lens array. They may, for example, first be connected to theelectrical pathways 56 of the PCB, whereby a flexible adhesive may be provided between thesecond surfaces 37 of theLEDs 34 and the top surface of the PCB. Subsequently, themulti-lens array 40 may be put in place, such that itsplano side 46 presses gently against the light-emittingsurfaces 36 of theLEDs 34 to align them in the z-direction. When allLEDs 34 are properly aligned, the flexible adhesive may be cured to permanently fix the relative orientations of the LEDs. An advantage of the first embodiment is that theLEDs 34 are fixed to themulti-lens array 40 with high positional accuracy. Accordingly, no separate alignment of theLEDs 34 and themulti-lens array 40 is necessary, and differences in thermal expansion coefficients between the multi-lens array on the one hand, and the support body and/or the PCB on the other, can no longer cause misalignment of the LEDs relative to the multi-lens array. -
FIGS. 5A and 5B show a schematic side view and a perspective view respectively, of a furtherembodiment having slots 55 accommodatingPCB 56, whereas theribs 54 between theslots 55 provide for mechanical support of theLEDs 34. It is shown thatmultiple LEDS 34 may be provided on thesurface 52; which are groupwise controlled by electrical circuitry arranged on thePCB 56 in theslots 55. This provides a thermal benefit as the LEDs are not each positioned on narrow ribs dimensioned to the LED interdistance, which could otherwise limit thermal conductivity to thecooling channels 60. - The
electrical pathway structures 56 on PCB may be stacked in a vertical configuration, that is, the PCB extending in a plane transverse to the levellingsurface 52. This optimizes the gap distance which can be kept minimal betweensubsequent LEDs 34. - In this way, by using
slot 55 to expand a planar region of the PCB, a mere single or two -layer PCB structure is sufficient to provide all the electronic pathways from the LEDs to the ICs 57. - In addition by arranging a driver circuit 57 in the
slot 55, a distance between driver ICs 57 and LEDs can be shortened. The illustratedPCB structure 56 extends in addition, in the preferred embodiment in the plane of the levellingsurface 56, and hasopenings 59 to accommodateLEDs 34 that are directly provided on the levelling surface. - The openings are made substantially larger than the size of the LEDs, such that the tolerance on the position of the PCB with respect to the LEDs is high. The
PCB 56 is a flex type PCB and is folded such that at least the part with ICs 57 fits in theslots 55 and the part with the holes for the LEDs lies flat on thesubstrate 50. - Although illustrative embodiments of the present invention have been described with reference to the accompanying drawings, it is to be understood that the invention is not limited to these embodiments. Various changes or modifications may be effected by one skilled in the art without departing from the scope or the spirit of the invention as defined in the claims. Furthermore, it is noted that application of the illumination system described above is not limited to the field of stereolithography. It may, for example, also be applied in other fields of the printing industry.
- 1 Stereolithography apparatus (SLA)
- 2 Tangible object
- 4 Carrier plate
- 6 Direction of movement of carrier plate
- 8 Direction of movement of illumination system
- 10 Liquid reservoir
- 12 Bottom plate of liquid reservoir
- 14 Photo-curable resin
- 16 Liquid layer
- 18 Solid layer of
tangible object 2 - 30 Illumination system
- 32 LED array
- 34 LED
- 36 Light-emitting surface of LED
- 38 Controller
- 40 Multi-lens array
- 42 Multi-lens array
- 44 Lens
- 46 Plano side of lens
- 48 Convex side of lens
- 50 Support body
- 52 Support body surface
- 54 Rib
- 56 Electrical pathways
- 58 Wire bond
- 60 Cooling channels
Claims (18)
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP09151794.6 | 2009-01-30 | ||
EP09151794 | 2009-01-30 | ||
EP09151794A EP2218571A1 (en) | 2009-01-30 | 2009-01-30 | Illumination system for use in a stereolithography apparatus |
PCT/NL2010/050043 WO2010087708A1 (en) | 2009-01-30 | 2010-01-29 | Illumination system for use in a stereolithography apparatus |
Publications (2)
Publication Number | Publication Date |
---|---|
US20120106150A1 true US20120106150A1 (en) | 2012-05-03 |
US8915620B2 US8915620B2 (en) | 2014-12-23 |
Family
ID=40863603
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/146,858 Active US8915620B2 (en) | 2009-01-30 | 2010-01-29 | Illumination system for use in a stereolithography apparatus |
Country Status (10)
Country | Link |
---|---|
US (1) | US8915620B2 (en) |
EP (2) | EP2218571A1 (en) |
JP (1) | JP5555720B2 (en) |
KR (1) | KR20110113739A (en) |
CN (1) | CN102300698B (en) |
BR (1) | BRPI1007004A2 (en) |
CA (1) | CA2750587C (en) |
ES (1) | ES2419704T3 (en) |
RU (1) | RU2540585C2 (en) |
WO (1) | WO2010087708A1 (en) |
Cited By (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20150056320A1 (en) * | 2012-07-27 | 2015-02-26 | Dws S.R.L. | Cartridge for a stereolithographic machine, sterolithographic machine comprising said cartridge and method of manufacturing said cartridge |
WO2016077250A1 (en) * | 2014-11-10 | 2016-05-19 | Velo3D, Inc. | Systems, apparatuses and methods for generating three-dimensional objects with scaffold features |
US9346127B2 (en) | 2014-06-20 | 2016-05-24 | Velo3D, Inc. | Apparatuses, systems and methods for three-dimensional printing |
WO2016153106A1 (en) * | 2015-03-20 | 2016-09-29 | Lg Electronics Inc. | 3d printing apparatus |
US9662840B1 (en) | 2015-11-06 | 2017-05-30 | Velo3D, Inc. | Adept three-dimensional printing |
US9873223B2 (en) | 2014-10-05 | 2018-01-23 | X Development Llc | Shifting a curing location during 3D printing |
US9919360B2 (en) | 2016-02-18 | 2018-03-20 | Velo3D, Inc. | Accurate three-dimensional printing |
DE102016118996A1 (en) * | 2016-10-06 | 2018-04-12 | Osram Opto Semiconductors Gmbh | MANUFACTURE OF SENSORS |
US9962767B2 (en) | 2015-12-10 | 2018-05-08 | Velo3D, Inc. | Apparatuses for three-dimensional printing |
US20180126649A1 (en) | 2016-11-07 | 2018-05-10 | Velo3D, Inc. | Gas flow in three-dimensional printing |
US10144176B1 (en) | 2018-01-15 | 2018-12-04 | Velo3D, Inc. | Three-dimensional printing systems and methods of their use |
US10252336B2 (en) | 2016-06-29 | 2019-04-09 | Velo3D, Inc. | Three-dimensional printing and three-dimensional printers |
WO2019079450A1 (en) | 2017-10-20 | 2019-04-25 | Formlabs, Inc. | Techniques for application of light in additive fabrication and related systems and methods |
US10272525B1 (en) | 2017-12-27 | 2019-04-30 | Velo3D, Inc. | Three-dimensional printing systems and methods of their use |
US10315252B2 (en) | 2017-03-02 | 2019-06-11 | Velo3D, Inc. | Three-dimensional printing of three-dimensional objects |
US10449696B2 (en) | 2017-03-28 | 2019-10-22 | Velo3D, Inc. | Material manipulation in three-dimensional printing |
US10611092B2 (en) | 2017-01-05 | 2020-04-07 | Velo3D, Inc. | Optics in three-dimensional printing |
US10792859B2 (en) * | 2013-11-14 | 2020-10-06 | Structo Pte Ltd | Additive manufacturing device and method |
US11396133B2 (en) | 2018-06-01 | 2022-07-26 | Formlabs, Inc. | Techniques for directing light from a movable stage in additive fabrication and related systems and methods |
US11691343B2 (en) | 2016-06-29 | 2023-07-04 | Velo3D, Inc. | Three-dimensional printing and three-dimensional printers |
Families Citing this family (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8777602B2 (en) | 2008-12-22 | 2014-07-15 | Nederlandse Organisatie Voor Tobgepast-Natuurwetenschappelijk Onderzoek TNO | Method and apparatus for layerwise production of a 3D object |
US8678805B2 (en) | 2008-12-22 | 2014-03-25 | Dsm Ip Assets Bv | System and method for layerwise production of a tangible object |
BRPI0923627A2 (en) | 2008-12-22 | 2016-01-19 | Nl Organisate Voor Toegepast Natuurwetenchappelijk Onderzoek Tno | method and system for layered production of a tangible object |
ITVI20110302A1 (en) * | 2011-11-23 | 2013-05-24 | Dws Srl | PERFECTED THREE-DIMENSIONAL OBJECT OBTAINED THROUGH A STEREOLITHOGRAPHIC PROCEDURE AND METHOD FOR THE DESIGN OF COMPUTERIZED GRAPHICS |
WO2016204814A1 (en) * | 2015-06-15 | 2016-12-22 | Halliburton Energy Services, Inc. | Downhole tools comprising aqueous-degradable sealing elements of thermoplastic rubber |
JP2017530251A (en) * | 2014-07-09 | 2017-10-12 | アプライド マテリアルズ インコーポレイテッドApplied Materials,Incorporated | Layered heating, line-by-line heating, plasma heating, and multiple feed materials in additive manufacturing |
GB201413578D0 (en) * | 2014-07-31 | 2014-09-17 | Infiniled Ltd | A colour iled display on silicon |
US9840045B2 (en) | 2014-12-31 | 2017-12-12 | X Development Llc | Voxel 3D printer |
GB201501382D0 (en) | 2015-01-28 | 2015-03-11 | Structo Pte Ltd | Additive manufacturing device with release mechanism |
GB201508178D0 (en) * | 2015-05-13 | 2015-06-24 | Photocentric Ltd | Method for making an object |
ITUB20154169A1 (en) | 2015-10-02 | 2017-04-02 | Thelyn S R L | Self-lubricating substrate photo-hardening method and apparatus for the formation of three-dimensional objects. |
DE102016121047B4 (en) * | 2015-11-06 | 2021-07-01 | Lisa Dräxlmaier GmbH | MANUFACTURING PROCESS FOR A LIGHTING DEVICE |
CN110225813A (en) * | 2017-01-25 | 2019-09-10 | 耐克森三维有限公司 | Use the method and apparatus that the light engine of three-dimension object is formed for optical solidified liquid polymer |
EP3820678B1 (en) | 2018-07-10 | 2023-06-14 | 3D Systems, Inc. | Three dimensional (3d) printer and method |
KR101990431B1 (en) * | 2018-11-09 | 2019-06-19 | 주식회사 쓰리딜라이트 | 3D Printer using macro led |
CN114829113A (en) | 2019-10-14 | 2022-07-29 | 速科特私人有限公司 | Radiation system and method for additive manufacturing |
CN111605191A (en) * | 2020-06-24 | 2020-09-01 | 深圳市智能派科技有限公司 | Multi-size photocuring 3D printer concatenation light source |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5173759A (en) * | 1990-02-06 | 1992-12-22 | Kyocera Corporation | Array of light emitting devices or photo detectors with marker regions |
US5317344A (en) * | 1989-12-22 | 1994-05-31 | Eastman Kodak Company | Light emitting diode printhead having improved signal distribution apparatus |
US5655189A (en) * | 1994-05-27 | 1997-08-05 | Kyocera Corporation | Image device having thermally stable light emitting/receiving arrays and opposing lenses |
US6214432B1 (en) * | 1999-06-02 | 2001-04-10 | Sony Corporation, | Method for controlling the bonding layer thickness in an optical storage apparatus and optical storage apparatus resulting therefrom |
US20050057641A1 (en) * | 2003-09-17 | 2005-03-17 | Mitsuhiko Ogihara | Combined semiconductor device, LED print head, and image forming apparatus |
WO2006095949A1 (en) * | 2005-03-11 | 2006-09-14 | Seoul Semiconductor Co., Ltd. | Led package having an array of light emitting cells coupled in series |
US20080038396A1 (en) * | 2006-04-28 | 2008-02-14 | Envisiontec Gmbh | Device and method for producing a three-dimensional object by means of mask exposure |
US20090115833A1 (en) * | 2007-09-14 | 2009-05-07 | Soulliaert Eric | Light emitting array for printing or copying |
Family Cites Families (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0435178Y2 (en) * | 1986-06-26 | 1992-08-20 | ||
JPS636853A (en) | 1986-06-26 | 1988-01-12 | Nec Corp | Multipin ceramic integrated circuit device |
US4942405A (en) | 1988-10-11 | 1990-07-17 | Hewlett-Packard Company | Light emitting diode print head assembly |
US5175612A (en) | 1989-12-19 | 1992-12-29 | Lsi Logic Corporation | Heat sink for semiconductor device assembly |
JP2805534B2 (en) * | 1990-06-30 | 1998-09-30 | 京セラ株式会社 | Image element array chip mounting method |
US5453145A (en) | 1991-03-04 | 1995-09-26 | Eastman Kodak Company | Z-axis dimensional control in manufacturing an LED printhead |
JPH05323230A (en) * | 1992-05-26 | 1993-12-07 | Kyocera Corp | Image device |
US5857767A (en) | 1996-09-23 | 1999-01-12 | Relume Corporation | Thermal management system for L.E.D. arrays |
JP4145978B2 (en) | 1997-11-11 | 2008-09-03 | ナブテスコ株式会社 | Stereolithography apparatus and method |
RU2189523C2 (en) * | 1998-12-30 | 2002-09-20 | Открытое акционерное общество "ЛОМО" | Light-emitting diode lighting unit |
JP2001063142A (en) * | 1999-08-31 | 2001-03-13 | Sanyo Electric Co Ltd | Led print head and method for correcting height of chip array |
CA2332190A1 (en) * | 2001-01-25 | 2002-07-25 | Efos Inc. | Addressable semiconductor array light source for localized radiation delivery |
JP4955422B2 (en) * | 2006-03-08 | 2012-06-20 | 三菱電機株式会社 | Light emitting device |
WO2008081846A1 (en) * | 2006-12-26 | 2008-07-10 | Kyocera Corporation | Optical printer head and image forming apparatus provided with the same |
-
2009
- 2009-01-30 EP EP09151794A patent/EP2218571A1/en not_active Withdrawn
-
2010
- 2010-01-29 BR BRPI1007004A patent/BRPI1007004A2/en not_active IP Right Cessation
- 2010-01-29 CN CN201080005957.5A patent/CN102300698B/en not_active Expired - Fee Related
- 2010-01-29 RU RU2011135992/05A patent/RU2540585C2/en not_active IP Right Cessation
- 2010-01-29 WO PCT/NL2010/050043 patent/WO2010087708A1/en active Application Filing
- 2010-01-29 EP EP10702553.8A patent/EP2391498B1/en not_active Not-in-force
- 2010-01-29 JP JP2011547842A patent/JP5555720B2/en not_active Expired - Fee Related
- 2010-01-29 CA CA2750587A patent/CA2750587C/en active Active
- 2010-01-29 ES ES10702553T patent/ES2419704T3/en active Active
- 2010-01-29 US US13/146,858 patent/US8915620B2/en active Active
- 2010-01-29 KR KR1020117018026A patent/KR20110113739A/en not_active Application Discontinuation
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5317344A (en) * | 1989-12-22 | 1994-05-31 | Eastman Kodak Company | Light emitting diode printhead having improved signal distribution apparatus |
US5173759A (en) * | 1990-02-06 | 1992-12-22 | Kyocera Corporation | Array of light emitting devices or photo detectors with marker regions |
US5655189A (en) * | 1994-05-27 | 1997-08-05 | Kyocera Corporation | Image device having thermally stable light emitting/receiving arrays and opposing lenses |
US6214432B1 (en) * | 1999-06-02 | 2001-04-10 | Sony Corporation, | Method for controlling the bonding layer thickness in an optical storage apparatus and optical storage apparatus resulting therefrom |
US20050057641A1 (en) * | 2003-09-17 | 2005-03-17 | Mitsuhiko Ogihara | Combined semiconductor device, LED print head, and image forming apparatus |
WO2006095949A1 (en) * | 2005-03-11 | 2006-09-14 | Seoul Semiconductor Co., Ltd. | Led package having an array of light emitting cells coupled in series |
US20080038396A1 (en) * | 2006-04-28 | 2008-02-14 | Envisiontec Gmbh | Device and method for producing a three-dimensional object by means of mask exposure |
US20090115833A1 (en) * | 2007-09-14 | 2009-05-07 | Soulliaert Eric | Light emitting array for printing or copying |
Cited By (57)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9555584B2 (en) * | 2012-07-27 | 2017-01-31 | Dws S.R.L. | Stereolithography machine with cartridge containing a reservoir |
US20150056320A1 (en) * | 2012-07-27 | 2015-02-26 | Dws S.R.L. | Cartridge for a stereolithographic machine, sterolithographic machine comprising said cartridge and method of manufacturing said cartridge |
US10766243B2 (en) | 2012-07-27 | 2020-09-08 | Dws S.R.L. | Cartridge for a stereolithographic machine, stereo-lithographic machine comprising said cartridge and method of manufacturing said cartridge |
US11628616B2 (en) | 2013-11-14 | 2023-04-18 | Structo Pte Ltd | Additive manufacturing device and method |
US10792859B2 (en) * | 2013-11-14 | 2020-10-06 | Structo Pte Ltd | Additive manufacturing device and method |
US11400645B2 (en) | 2013-11-14 | 2022-08-02 | Structo Pte Ltd | Additive manufacturing device and method |
US9403235B2 (en) | 2014-06-20 | 2016-08-02 | Velo3D, Inc. | Apparatuses, systems and methods for three-dimensional printing |
US9486878B2 (en) | 2014-06-20 | 2016-11-08 | Velo3D, Inc. | Apparatuses, systems and methods for three-dimensional printing |
US9573225B2 (en) | 2014-06-20 | 2017-02-21 | Velo3D, Inc. | Apparatuses, systems and methods for three-dimensional printing |
US9573193B2 (en) | 2014-06-20 | 2017-02-21 | Velo3D, Inc. | Apparatuses, systems and methods for three-dimensional printing |
US9586290B2 (en) | 2014-06-20 | 2017-03-07 | Velo3D, Inc. | Systems for three-dimensional printing |
US10195693B2 (en) | 2014-06-20 | 2019-02-05 | Vel03D, Inc. | Apparatuses, systems and methods for three-dimensional printing |
US9399256B2 (en) | 2014-06-20 | 2016-07-26 | Velo3D, Inc. | Apparatuses, systems and methods for three-dimensional printing |
US9821411B2 (en) | 2014-06-20 | 2017-11-21 | Velo3D, Inc. | Apparatuses, systems and methods for three-dimensional printing |
US9346127B2 (en) | 2014-06-20 | 2016-05-24 | Velo3D, Inc. | Apparatuses, systems and methods for three-dimensional printing |
US10507549B2 (en) | 2014-06-20 | 2019-12-17 | Velo3D, Inc. | Apparatuses, systems and methods for three-dimensional printing |
US10493564B2 (en) | 2014-06-20 | 2019-12-03 | Velo3D, Inc. | Apparatuses, systems and methods for three-dimensional printing |
US9873223B2 (en) | 2014-10-05 | 2018-01-23 | X Development Llc | Shifting a curing location during 3D printing |
WO2016077250A1 (en) * | 2014-11-10 | 2016-05-19 | Velo3D, Inc. | Systems, apparatuses and methods for generating three-dimensional objects with scaffold features |
WO2016153106A1 (en) * | 2015-03-20 | 2016-09-29 | Lg Electronics Inc. | 3d printing apparatus |
US10357957B2 (en) | 2015-11-06 | 2019-07-23 | Velo3D, Inc. | Adept three-dimensional printing |
US10065270B2 (en) | 2015-11-06 | 2018-09-04 | Velo3D, Inc. | Three-dimensional printing in real time |
US9662840B1 (en) | 2015-11-06 | 2017-05-30 | Velo3D, Inc. | Adept three-dimensional printing |
US9676145B2 (en) | 2015-11-06 | 2017-06-13 | Velo3D, Inc. | Adept three-dimensional printing |
US10688722B2 (en) | 2015-12-10 | 2020-06-23 | Velo3D, Inc. | Skillful three-dimensional printing |
US10286603B2 (en) | 2015-12-10 | 2019-05-14 | Velo3D, Inc. | Skillful three-dimensional printing |
US10207454B2 (en) | 2015-12-10 | 2019-02-19 | Velo3D, Inc. | Systems for three-dimensional printing |
US10058920B2 (en) | 2015-12-10 | 2018-08-28 | Velo3D, Inc. | Skillful three-dimensional printing |
US10071422B2 (en) | 2015-12-10 | 2018-09-11 | Velo3D, Inc. | Skillful three-dimensional printing |
US9962767B2 (en) | 2015-12-10 | 2018-05-08 | Velo3D, Inc. | Apparatuses for three-dimensional printing |
US10183330B2 (en) | 2015-12-10 | 2019-01-22 | Vel03D, Inc. | Skillful three-dimensional printing |
US9931697B2 (en) | 2016-02-18 | 2018-04-03 | Velo3D, Inc. | Accurate three-dimensional printing |
US10252335B2 (en) | 2016-02-18 | 2019-04-09 | Vel03D, Inc. | Accurate three-dimensional printing |
US10434573B2 (en) | 2016-02-18 | 2019-10-08 | Velo3D, Inc. | Accurate three-dimensional printing |
US9919360B2 (en) | 2016-02-18 | 2018-03-20 | Velo3D, Inc. | Accurate three-dimensional printing |
US11691343B2 (en) | 2016-06-29 | 2023-07-04 | Velo3D, Inc. | Three-dimensional printing and three-dimensional printers |
US10252336B2 (en) | 2016-06-29 | 2019-04-09 | Velo3D, Inc. | Three-dimensional printing and three-dimensional printers |
US10259044B2 (en) | 2016-06-29 | 2019-04-16 | Velo3D, Inc. | Three-dimensional printing and three-dimensional printers |
US10286452B2 (en) | 2016-06-29 | 2019-05-14 | Velo3D, Inc. | Three-dimensional printing and three-dimensional printers |
DE102016118996A1 (en) * | 2016-10-06 | 2018-04-12 | Osram Opto Semiconductors Gmbh | MANUFACTURE OF SENSORS |
US10749055B2 (en) | 2016-10-06 | 2020-08-18 | Osram Oled Gmbh | Production of sensors |
US10661341B2 (en) | 2016-11-07 | 2020-05-26 | Velo3D, Inc. | Gas flow in three-dimensional printing |
US20180126649A1 (en) | 2016-11-07 | 2018-05-10 | Velo3D, Inc. | Gas flow in three-dimensional printing |
US10611092B2 (en) | 2017-01-05 | 2020-04-07 | Velo3D, Inc. | Optics in three-dimensional printing |
US10357829B2 (en) | 2017-03-02 | 2019-07-23 | Velo3D, Inc. | Three-dimensional printing of three-dimensional objects |
US10369629B2 (en) | 2017-03-02 | 2019-08-06 | Veo3D, Inc. | Three-dimensional printing of three-dimensional objects |
US10888925B2 (en) | 2017-03-02 | 2021-01-12 | Velo3D, Inc. | Three-dimensional printing of three-dimensional objects |
US10315252B2 (en) | 2017-03-02 | 2019-06-11 | Velo3D, Inc. | Three-dimensional printing of three-dimensional objects |
US10442003B2 (en) | 2017-03-02 | 2019-10-15 | Velo3D, Inc. | Three-dimensional printing of three-dimensional objects |
US10449696B2 (en) | 2017-03-28 | 2019-10-22 | Velo3D, Inc. | Material manipulation in three-dimensional printing |
WO2019079450A1 (en) | 2017-10-20 | 2019-04-25 | Formlabs, Inc. | Techniques for application of light in additive fabrication and related systems and methods |
EP3697595A4 (en) * | 2017-10-20 | 2021-07-28 | Formlabs, Inc. | Techniques for application of light in additive fabrication and related systems and methods |
US11305483B2 (en) * | 2017-10-20 | 2022-04-19 | Formlabs, Inc. | Techniques for application of light in additive fabrication and related systems and methods |
US11820074B2 (en) | 2017-10-20 | 2023-11-21 | Formlabs, Inc. | Techniques for application of light in additive fabrication and related systems and methods |
US10272525B1 (en) | 2017-12-27 | 2019-04-30 | Velo3D, Inc. | Three-dimensional printing systems and methods of their use |
US10144176B1 (en) | 2018-01-15 | 2018-12-04 | Velo3D, Inc. | Three-dimensional printing systems and methods of their use |
US11396133B2 (en) | 2018-06-01 | 2022-07-26 | Formlabs, Inc. | Techniques for directing light from a movable stage in additive fabrication and related systems and methods |
Also Published As
Publication number | Publication date |
---|---|
KR20110113739A (en) | 2011-10-18 |
RU2540585C2 (en) | 2015-02-10 |
CA2750587C (en) | 2019-05-14 |
EP2218571A1 (en) | 2010-08-18 |
CN102300698A (en) | 2011-12-28 |
BRPI1007004A2 (en) | 2016-03-22 |
US8915620B2 (en) | 2014-12-23 |
EP2391498A1 (en) | 2011-12-07 |
CA2750587A1 (en) | 2010-08-05 |
JP5555720B2 (en) | 2014-07-23 |
EP2391498B1 (en) | 2013-05-15 |
ES2419704T3 (en) | 2013-08-21 |
RU2011135992A (en) | 2013-03-10 |
WO2010087708A1 (en) | 2010-08-05 |
JP2012516539A (en) | 2012-07-19 |
CN102300698B (en) | 2014-06-04 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US8915620B2 (en) | Illumination system for use in a stereolithography apparatus | |
CN102414624B (en) | Illumination system for use in a stereolithography apparatus | |
JP2022133477A (en) | Laser diode module, device, and method for making chip on submount module | |
US9149964B2 (en) | Method of molding, process for producing lens, molding apparatus, process for producing stamper, master production apparatus, stamper production system, and stamper production apparatus | |
KR20000070084A (en) | Optical formation device and method | |
US4942405A (en) | Light emitting diode print head assembly | |
US5014074A (en) | Light emitting diode print head assembly | |
US20240109251A1 (en) | Irradiation systems and method for additive manufacturing | |
US6894315B2 (en) | Structure of light-emitting diode array module | |
JP2010177306A (en) | Led board device and led printhead | |
US11013119B2 (en) | Component carrier with deformed layer for accommodating component | |
KR102294340B1 (en) | Led illuminating apparatus with high radiation angle of light using three-dimensional printing process and method for manufacturing the same | |
JP2003078219A (en) | Recessed printed wiring board and its manufacturing method | |
CN116277938A (en) | Photo-curing 3D printer and printing method |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: NEDERLANDSE ORGANISATIE VOOR TOEGEPAST-NATUURWETEN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:VAES, MARK HERMAN ELSE;MAALDERINK, HERMAN HENDRIKUS;VERMEER, ADRIANUS JOHANNES PETRUS MARIA;AND OTHERS;SIGNING DATES FROM 20110901 TO 20110930;REEL/FRAME:027024/0131 |
|
STCF | Information on status: patent grant |
Free format text: PATENTED CASE |
|
FEPP | Fee payment procedure |
Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
MAFP | Maintenance fee payment |
Free format text: PAYMENT OF MAINTENANCE FEE, 4TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M1551) Year of fee payment: 4 |
|
MAFP | Maintenance fee payment |
Free format text: PAYMENT OF MAINTENANCE FEE, 8TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M1552); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY Year of fee payment: 8 |